REPORT ON ZOOLOGY. 151 



and that the former live within their vertebral column, in the 

 same manner as the latter do tvithout. It is clear that, assiun- 

 ing the correctness of these views, it becomes necessarj'^ to make 

 some alteration in the leading divisions of Cmder's system. The 

 following is the arrangement proposed by Geotfroy : 



rv f K ' / Hants- Vertebres. {Vertebres, C\xv.) 

 I verteDves. j Dermo-Vert6br^s. {ArticvUs, Cuv.) 

 Aiiimaux < ,., , ( Mollusques. {Mollusques, Cuv.) 



( inverteDres. | R^yonn^s. {Rayonnes, Cuv.) 



Thus we have a primary division into vertebrate and inverte- 

 brate animals, before arriving at Cuvier's four types, talcing 

 however the term vertebrate in a much more extended sense 

 than did Lamarck, or any other previous author, and likewise 

 that of invertebrate in a more restricted one. Geoffroy's me- 

 moirs on this subject were published, as already stated, in 1820, 

 in the Jonrnal Complementaire* , &c. He subsequently fol- 

 lowed up the same views in some other publications, more 

 especially in a paper in the 3Iem. du Mas. for 1822t, in which 

 he entered into a strict analysis of the structure of the -vertebra, 

 first as it occurs in the higher animals, and afterwards as it ap- 

 pears, though modified, in the segments of the AnmdosaX. His 

 theory, I believe, has been adopted by many of the French and 

 German naturalists, as well as by some in other countries. 

 Amongst the former, I may particularly mention Robineau- 

 Desvoidy, who in 1828 published a work§ in order to substan- 

 tiate, by still further illustration, the vertebral structure of the 

 Crustacea, Arachnida, and Insecta. Towards the conclusion, he 

 has pointed out the necessity (as it appears to him) of institut- 

 ing several new classes amongst the annulose animals. It may 

 be much doubted, however, whether these new classes will ever 

 be adopted generally, whatever may be the fate of those theore- 

 tical views which have alone suggested them ||. 



, * " M^moires sur 1 'Organisation des Insectes," Journ. CompUm. du Diet, 

 des Set. Med., torn. v. p. 340; and torn. vi. pp. 31 and 138. 



+ tom.ix. 



X See also his Cours de V Hist. Nat. des Mammiferes, Le^. o^, published in 

 1829. 



§ Rec/ierches sur V Organisation vertehrale des Crustaces, des Ai-achnides, et 

 des Insectes. Paris, 1828, Svo. 



II As connected with the subject of the differences and resemblances between 

 vertebrate and invertebrate animals, I ma)' refer to two recent memoirs, of 

 which abstracts will be found in L'lnstitttt. The first, entitled " Recherches sur 

 les Parties dures des Animaux Invertebres, par M. Dupuy," was read to the Aca- 

 dem5' at Toulouse, Jan. 1833. {L'Institut, 1833, p. 3.) ' The other is a memoir 

 by Dutrochet, " Sur I'Opposition qui existe entre les Animaux Vertebres et les 

 Animaux Invertebres," read to the Academy of Sciences at Paris in March 

 last. (See L'Jnstit. 1834, p. 90.) 



